The objective of this study was to evaluate and compare physical parameters in groups of sheep with different phenotypic characteristics in the Centre-west region of Brazil. Five groups of sheep, with nine animals per group, were selected, three groups of Santa Inês animals with different coat colours (white, brown and black), one group with crossbred animals (Santa Inês × Bergamasca) and one group with animals of the Bergamasca breed. The following traits were evaluated: coat thickness, number and length of hair, pigmentation level in the coat and the skin as well as the percentage area of sweats glands in the skin tissue, carried out by histological analysis. The number of hairs and the area of sweats glands were not significantly different between the evaluated groups. The Bergamasca breed showed low pigmentation of the skin and long hairs. The levels of pigmentation of the hair and of the skin were highly correlated. Between the Santa Inês groups, the group with white hair showed the better parameters for heat adaptation, while the brown hair group showed the lower heat adaptation when compared with another hair breed groups.

A intensificação da produção de tilápias pode gerar implicações negativas sobre o desempenho e o bem-estar dos peixes. Assim, é essencial determinar a densidade correta para otimizar a produção. O objetivo deste estudo foi avaliar o desempenho e o bem-estar de tilápias-do-nilo (Oreochromis niloticus) juvenis, com peso inicial médio de 30g (± 2,70), criadas em três diferentes densidades de estocagem, em gaiolas de flutuação. Os peixes foram alimentados três vezes/dia, com ração contendo 32% de proteína bruta, durante 74 dias. O desenho experimental foi completamente ao acaso, com três tratamentos (250 peixes/m3, 350 peixes/m3 e 450 peixes/m3) e quatro réplicas. Os parâmetros físico-químicos da água foram monitorados durante o experimento. A elevação da densidade de criação causou redução no peso final dos peixes, no ganho de peso, no ganho de peso diário, no comprimento padrão e na taxa de sobrevivência, bem como elevou a taxa de conversão alimentar. Entretanto, densidades mais elevadas reduziram o efeito na variação de peso. Não houve influência da densidade de criação nos parâmetros de biomassa final, da concentração de glicose sanguínea e de cortisol sérico. Portanto, o aumento na densidade de criação compromete o desenvolvimento e a taxa de sobrevivência dos peixes, mas não influencia os parâmetros fisiológicos de estresse. Assim, o tratamento com 250 peixes/m3 apresentou resultados mais apropriados ao melhor desempenho dos peixes.

Flooded areas of reservoirs and artificial lakes have been increasingly used for fish production; however, the waste generated by aquaculture has become a concern for the sustainable development of this activity. One of the main strategies adopted by management and regulatory agencies is the use of hydrodynamic models that calculate the carrying or nutrient load capacity of a particular water body and the effect of fish farming. These models are precise in the development of optimal strategies for feeding and waste calculation. This review paper addresses this topic and describes the methodology developed for the analysis and simulation of the carrying capacity for fish production, based on the integration of the Fish-PrFEQ nutritional bioenergetic model and the hydrodynamic model of Dillon & Rigler. This methodology allows evaluating the real contribution of aquaculture waste and assists in the planning and management of aquaculture in these aquatic environments, besides enabling and encouraging producers and the aquaculture industry to use fish food with better nutritional quality and lower environmental impact.

This research aims to evaluate the microclimate of commercial loads of broiler chickens at different distances in the summer (rainy) and winter (dry)

This study compared the adaptation traits in common crosses of crossbred dairy cattle in central Brazil. Twenty animals of each of three genetic groups were used: zebu (Bos indicus), Simmental x Zebu (SZ) and Holstein x Zebu (HZ). The test measured variations in rectal temperature (RT), respiration rate (RR) and heart rate (HR) of animals in the shade and after exposure to the sun, as well as mean daily milk production throughout the lactation period. The procedure was repeated three times. There were significant interactions between test group and genetic group for the traits investigated and the correlations among traits were low. The RR of the crossbred groups may be controlling body temperature in such a way as not to cause an increase in RT. Milk production influenced RR in crossbred cows exposed to the sun, confirming their poorer adaptation in comparison with zebu cows. We observed that the adaptation can be measured in terms of production within the same genetic group. In conclusion, the crosses with European breeds produced more milk than zebu, although they were influenced by heat/solar radiation.

1. This study was conducted to verify the impact of different kinds of material and the number of times of litter reuse on the incidence of chicken pathologies. Approximately 4·5 million broilers from conventional Brazilian farms were evaluated in the abattoir for cellulitis, arthritis and contact foot-pad dermatitis. 2. Four different kinds of litter material, Brachiaria grass, corncob, sawdust and rice shell, were used. Brachiaria grass litter showed the highest incidence of contact foot-pad dermatitis. Corncob litter also showed some negative effects on foot quality. Broilers raised on rice shell litter showed good results in terms of the incidence of contact foot-pad dermatitis. The best results were obtained with sawdust litter, because the incidence of cellulitis and arthritis were the lowest and the incidence of contact foot-pad dermatitis was also very low.